cc1: warnings being treated as errors
/build/src/sys/kern/subr_autoconf.c: In function 'deviter_init':

/build/src/sys/kern/subr_autoconf.c:2255: warning: 'rw' is used uninitialized
in this function

1 error

This is a custom kernel config, but there's really nothing special about it.
It's just a very stripped-down version of GENERIC. The config file is
attached to this message just in case it does make a difference.